9 import Data.Maybe (fromJust)
10 import Test.HUnit (assertEqual)
11 import Test.Framework (Test, testGroup)
12 import Test.Framework.Providers.HUnit (testCase)
13 import Test.Framework.Providers.QuickCheck2 (testProperty)
14 import Test.QuickCheck (Arbitrary(..), Gen, Property, (==>))
20 -- | An Octet consists of eight bits. For our purposes, the most
21 -- significant bit will come "first." That is, b1 is in the 2^7
22 -- place while b8 is in the 2^0 place.
35 instance Show Octet where
36 show oct = show (fromEnum oct)
39 instance Arbitrary Octet where
41 a1 <- arbitrary :: Gen Bit
42 a2 <- arbitrary :: Gen Bit
43 a3 <- arbitrary :: Gen Bit
44 a4 <- arbitrary :: Gen Bit
45 a5 <- arbitrary :: Gen Bit
46 a6 <- arbitrary :: Gen Bit
47 a7 <- arbitrary :: Gen Bit
48 a8 <- arbitrary :: Gen Bit
49 return (Octet a1 a2 a3 a4 a5 a6 a7 a8)
52 instance Maskable Octet where
53 apply_mask oct Eight _ = oct
55 apply_mask oct Seven bit =
58 apply_mask oct Six bit =
59 oct { b8 = bit, b7 = bit }
61 apply_mask oct Five bit =
62 oct { b8 = bit, b7 = bit, b6 = bit }
64 apply_mask oct Four bit =
65 oct { b8 = bit, b7 = bit, b6 = bit, b5 = bit }
67 apply_mask oct Three bit =
68 oct { b8 = bit, b7 = bit, b6 = bit, b5 = bit, b4 = bit }
70 apply_mask oct Two bit =
71 oct { b8 = bit, b7 = bit, b6 = bit, b5 = bit, b4 = bit, b3 = bit }
73 apply_mask oct Maskbits.One bit =
74 oct { b8 = bit, b7 = bit, b6 = bit, b5 = bit,
75 b4 = bit, b3 = bit, b2 = bit }
77 apply_mask oct Maskbits.Zero bit =
78 oct { b8 = bit, b7 = bit, b6 = bit, b5 = bit,
79 b4 = bit, b3 = bit, b2 = bit, b1 = bit }
81 -- The Maskbits must be in [Eight..ThirtyTwo].
82 apply_mask oct _ _ = oct
85 instance Ord Octet where
86 (Octet x1 x2 x3 x4 x5 x6 x7 x8) <= (Octet y1 y2 y3 y4 y5 y6 y7 y8)
98 instance Bounded Octet where
99 -- | The octet with the least possible value.
101 Octet B.Zero B.Zero B.Zero B.Zero B.Zero B.Zero B.Zero B.Zero
103 -- | The octet with the greatest possible value.
105 Octet B.One B.One B.One B.One B.One B.One B.One B.One
108 instance Enum Octet where
109 -- We're supposed to throw a runtime error if you call (succ
110 -- maxBound), so the fromJust here doesn't introduce any additional
112 toEnum = fromJust . octet_from_int
114 -- | Convert each bit to its integer value, and multiply by the
115 -- appropriate power of two. Sum them up, and we should get an integer
116 -- between 0 and 255.
118 128 * (bit_to_int (b1 x)) +
119 64 * (bit_to_int (b2 x)) +
120 32 * (bit_to_int (b3 x)) +
121 16 * (bit_to_int (b4 x)) +
122 8 * (bit_to_int (b5 x)) +
123 4 * (bit_to_int (b6 x)) +
124 2 * (bit_to_int (b7 x)) +
125 1 * (bit_to_int (b8 x))
129 octet_from_int :: Int -> Maybe Octet
131 | (x < 0) || (x > 255) = Nothing
132 | otherwise = Just (Octet a1 a2 a3 a4 a5 a6 a7 a8)
134 a1 = if (x >= 128) then B.One else B.Zero
135 a2 = if ((x `mod` 128) >= 64) then B.One else B.Zero
136 a3 = if ((x `mod` 64) >= 32) then B.One else B.Zero
137 a4 = if ((x `mod` 32) >= 16) then B.One else B.Zero
138 a5 = if ((x `mod` 16) >= 8) then B.One else B.Zero
139 a6 = if ((x `mod` 8) >= 4) then B.One else B.Zero
140 a7 = if ((x `mod` 4) >= 2) then B.One else B.Zero
141 a8 = if ((x `mod` 2) == 1) then B.One else B.Zero
144 instance Read Octet where
146 case (reads s :: [(Int, String)]) of
148 (x,leftover):_ -> case (octet_from_int x) of
150 Just oct -> [(oct, leftover)]
156 testGroup "Octet Tests" [
157 test_octet_from_int1,
161 octet_properties :: Test
166 "fromEnum/toEnum are inverses"
167 prop_from_enum_to_enum_inverses,
169 "read/show are inverses"
170 prop_read_show_inverses ]
172 -- QuickCheck properties
173 prop_from_enum_to_enum_inverses :: Int -> Property
174 prop_from_enum_to_enum_inverses x =
175 (0 <= x) && (x <= 255) ==>
176 fromEnum (toEnum x :: Octet) == x
178 prop_read_show_inverses :: Int -> Property
179 prop_read_show_inverses x =
180 (0 <= x) && (x <= 255) ==> x' == x
189 test_octet_from_int1 :: Test
190 test_octet_from_int1 =
191 testCase desc $ assertEqual desc oct1 oct2
193 desc = "octet_from_int 128 should parse as 10000000"
194 oct1 = Octet B.One B.Zero B.Zero B.Zero B.Zero B.Zero B.Zero B.Zero
195 oct2 = fromJust $ octet_from_int 128
197 test_octet_mask1 :: Test
200 assertEqual desc oct2 (apply_mask oct1 Four B.Zero)
202 desc = "The network bits of 255/4 should equal 240"
203 oct1 = fromJust $ octet_from_int 255
204 oct2 = fromJust $ octet_from_int 240
207 test_octet_mask2 :: Test
210 assertEqual desc oct2 (apply_mask oct1 Maskbits.One B.Zero)
212 desc = "The network bits of 255/1 should equal 128"
213 oct1 = fromJust $ octet_from_int 255
214 oct2 = fromJust $ octet_from_int 128